Vehicles powered by internal combustion engines may be cooled by a coolant system, having coolant circulating in jackets surrounding combustion cylinders. The coolant may be heated by the engine and then cooled for recirculation by a heat exchanger, and the heat exchanger may be cooled by an air flow enhanced by a fan. The fan may be driven by an engine crankshaft, electrically driven by a vehicle electric system, or driven by a hydraulic system.
Some known methods for controlling a fan speed use coolant temperature signals for regulating, for example, a fan speed or blade pitch. For example, such a method my increase the fan speed or the blade pitch, as the coolant temperature increases and vice-versa. Such methods are reactive, rather than proactive.
In some operating conditions, the vehicle may operate in windy conditions. And during such conditions, if the vehicle is a work machine, for example, the vehicle may drive into the wind on one pass and drive with the wind on the next pass. When the vehicle drives into the wind, the fan and cooling system may provide adequate cooling and lower the coolant temperature. But when the vehicle drives with the wind, the fan and the cooling system may place a large load on engine and/or struggle to maintain reasonable coolant temperatures.